General Physics, 2nd Edition
2nd Edition
ISBN: 9780471522782
Author: Morton M. Sternheim
Publisher: WILEY
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Question
Chapter 18, Problem 6E
(a)
To determine
The membrane capacitance of myelinated segment of axon.
(b)
To determine
The membrane leakage resistance of myelinated segment of axon.
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12. (a) Using Eq. AQ=CAV and the data in the Table, calculate the number of ions entering the axon during
the action potential, per meter of nonmyelinated axon length. (The charge on the ion is 1.6 x 10-19 coulomb.)
(b) During the resting state of the axon, typical concentrations of sodium and potassium ions inside the axon
are 15 and 150 millimole/liter, respectively. From the data in the Table, calculate the number of ions per
meter length of the axon.
Table 13.1 Properties of Sample Axons
Hint:
1 F (farad) = 1coulomb/1 volt
Property
Nonmyelinated axon
Myelinated axon
Axon radius
5 x 10-m
5 x 10-6 m
1 mole /liter = 6.02 x 1020 particles (ions, atoms, etc. ) Resistance per unit length of fluid
cm
6.37 x 10°2/m
6.37 x 10°2/m
both inside and outside axon (r)
Conductivity per unit length of
axon membrane (gm)
1.25 x 10-4 mho/m
In the resting state, the axon voltage is -70mV.
During the pulse, the voltage changes to about
+30mV, resulting in a net voltage change across
the membrane of 100…
Assume an axon has the same characteristics as the class example
except the radius of the axon is 0.005 mm and the membrane
thickness is 20.0 nm. The percentage fractional change in the
concentration of Na+ ions in the axon during one action potential is
%? Record the answer to the nearest one
thousandth.
a) How does voltage change over distance from the stimulator on the artificial axon? AND why does this occur? (Think: where is the current going?)
b) How and why are neurons affected by the addition of myelin (think membrane resistance, capacitance, and the length constant)?
Chapter 18 Solutions
General Physics, 2nd Edition
Ch. 18 - Prob. 1RQCh. 18 - Prob. 2RQCh. 18 - Prob. 3RQCh. 18 - Prob. 4RQCh. 18 - Prob. 5RQCh. 18 - Prob. 6RQCh. 18 - Prob. 7RQCh. 18 - Prob. 8RQCh. 18 - Prob. 9RQCh. 18 - Prob. 10RQ
Ch. 18 - Prob. 1ECh. 18 - Prob. 2ECh. 18 - Prob. 3ECh. 18 - Prob. 4ECh. 18 - Prob. 5ECh. 18 - Prob. 6ECh. 18 - Prob. 7ECh. 18 - Prob. 8ECh. 18 - Prob. 9ECh. 18 - Prob. 10ECh. 18 - Prob. 11ECh. 18 - Prob. 12ECh. 18 - Prob. 13ECh. 18 - Prob. 14ECh. 18 - Prob. 15ECh. 18 - Prob. 16ECh. 18 - Prob. 17ECh. 18 - Prob. 18ECh. 18 - Prob. 20ECh. 18 - Prob. 21ECh. 18 - Prob. 24ECh. 18 - Prob. 25ECh. 18 - Prob. 26E
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